Appliance for testing the tension of textile threads or yarn



y 30, 1939- s. FURST 2,159,969

APPLIANCE FOR TESTING THE TENSION OF TEXTILE THREADS OR YARN Fild Dec. 14, 1937 4 Sheets-Sheet 1 May 30, 1939.

s. FpRsT APPLIANCE FOR TESTING THE TENSION OF TEXTILE THREADS OR YARN 4 Sheets-Sheet 2 Filed Dec. 14, 193'! S. FURST May 30, 1939.

APPLIANCE FOR TESTING THE TENSION OF TEXTILE THREADS OR YARN 4 Sheets-Sheet 3 Filed Dec. 14, 1937 May 30, 1939. s. FURST 2,159,969

APPLIANCE FOR TESTING THE TENSION OF TEXTILE THREADS OR YARN Filed Dec. 14, 1937 4 Sheets-Sheet 4 Patented May 30, l 939 UNITED STATES PATENT OFFICE APPLIANCE FOR TESTING THE TENSION OF TEXTILE THREADS OR YARN Application December 14, 1937, Serial No. 179,702 In Germany January 12, 1937 9 Claims.

The invention relates to appliances for testing the tension of a textile thread or yarn while the latter is in action in its machine.

In the case of known appliances of this kind designed to provide a record of the tension of the threads while they are being operated upon it is necessary that the inertia of the mechanism involved should be as small as possible, having regard tothe high speeds at which the threads travel. Purely mechanical means have not proved satisfactory and it has therefore been proposed to make tests by electric means, the record of the tension being produced with the aid of a cathode ray or other oscillograph. This method of measurement gives satisfactory results but is expensive. Moreover, such apparatus cannot be so designed as to be handy in use and enable ready access to be had to the different parts.

The object of the invention is to provide an appliance which will combine handiness with sensitiveness and simplicity of design, and it consists essentially of a springy feeler or contact member having a high natural vibration frequency which is adapted to be applied to the thread and has directly fixed thereto a mirror onto which there is projected a beam of light which is deflected to a varying extent in accordance with the movements of the mirror depending on the tension of the thread, and said reflected beam is focused onto travelling light-sensitive paper so that a graph of the tension is produced. The test may be made without interrupting the operation of the thread and at any part of the latter. Optical transmission has been ap plied to appliances of the kind hereinbefore described, but the reflection was not direct, other transmission means being introduced, which as a detrimental effect on the appliance as regards its sensitiveness and precision, and particularly 40 its simplicity of construction.

Embodiments of the invention are illustrated in the accompanying drawings wherein:

Fig. 1 shows the improved tension tester diagrammatically,

Fig. 2 is a sectional side view of the appliance;

Fig. 3 shows diagrammatically the appliance positioned for application to a thread to be tested.

Fig. 4 shows the parts illustrated in Fig. 3 in testing position, and set for maximum sensitiveness of the apparatus.

Fig. 5 shows a constructional form'of apparatus in plan, partly in section, and

Fig. 6 shows by way of example, one method of using the apparatus.

In all the figures l designates a source of light (electric light bulb), 2 a condensing lens, 3 a slit diaphragm, I a projection lens, 5 a thread feeler device, and 6 a spring armature for electromagnet II. A mirror 1 is rigidly fixed to the thread feeler 5, and a mirror 8 is rigidly fixed 5 to spring armature 6. The thread 9 to be tested is guided by the pulleys l0. Part of each beam reflected by the mirrors 1, 8 falls on a deflecting mirror l2 and thence onto visible scale l8 on a ground glass plate I, and the other part of 10 each beam passes through a piano-convex cylindrical lens l3, by which it is focused onto the light sensitive photographic paper l5. l6 designates a thread tension graph line produced on the paper and I! a normally continuous base line so long as electromagnet II is deenergized. By means, referred to later, a current pulse can be sent through the electromagnet winding, whereby its spring armature is momentarily attracted and thereby momentarily deflects mirror 3 and thus the light beam reflected thereby so that at given intervals kinks are produced in base line I"! as shown, for the purpose to be explained later. Referring to Fig. 2, in casing I9 is disposed a motor 20 which drives through a train of gears 2i, 22, 23, 24, 25, 26 a take-up reel 29 arranged to wind up the strip of sensitized paper l5 which passes over a paper guide roller 21 from a supply reel 28. A cover plate 30 provides an air-tight closure for the casing i9. The device 30 is controlled by a trigger lever 3| having a plurality of arms of which one on the right is provided with a rack 32 adapted to engage with a pinion 33, assumed to be connected with gear wheel 22 by a conventional overrunning clutch 85 (not shown), whilst the left arm of the trigger closes contact springs 35, 36 when the trigger is pulled. The purpose of rack 32 is to start motor 20, which is preferably of the non-selfstarting synchronous type, by which the speed 40 of paper strip I5 is maintained substantially-uniform. Trigger 3| is normally held in inoperative position by a tension spring 34. .As shown more clearly in Fig. 5, gear wheel 25 drives a gear wheel which in turn drives the reel 29 through a 45 drag clutch comprising a coil spring 46 disposed between a collar on the hollow hub of pinion 45 and the end of the hub of reel 29. Gear 45 with reel 29 and the reel 28 are carried by-screw studs 41 removably disposed in casing l9 to permit 50 exchange of the reels. The source of light I, the condensing lens 2, the slit diaphragm 3 and the projection lens 4 are mounted in a separate casing 31, disposed within casing IS. The spring feeler 5 and armature 6 are mounted both inside a bush 40 and spring feeler 5 extends into the hollow Ieeler finger 39 tapering to a point. The

guide fingers 38 located on either side of finger 39 contains the pulleys In. These latter fingers are in shape similar to finger 39. Fingers 38, 39 totally enclose the feeler 5 and pulleys l respectively, but for apertures, as shown in Fig. 2, which enable the thread to engage the hookshaped end (Fig; 1) of feeler and pulleys M respectively. The fingers 38 disposed one above and the other below the finger 39 are coupled together and mounted on trunnions carried at the outer end of main casing [9 so that they may be swung together towards or away from the finger 39. Fingers 38 can be diiferently positioned with respect to finger 39 and the degree of their adjustment is indicated by a pointer 42 biased by a spring 4| and working over a scale 44 on which the pointer can be locked by pin 43 against the 20 tension of spring 4|.

The operation of the device is as follows: The device, as shown in Fig. 6, is slipped for instance onto thread 11 whose tension is to be measured with fingers 38 in the position shown in Figs. 3 and 5, so that the thread can easily enter between fingers 38, 39 as shown in Fig. 3.'

Then the operator adjusts fingers 38 on scale 44 to the desired relative position withrespect to finger 39, according to whether he is testing a high or a low tensioned thread, for instance as shown in Fig. 4. If now trigger 3| is pulled, motor 20 is started as described and switch 35, 36 is closed which supplies current to the motor and lights lamp i. The beam from the source of light 1 passes through the condensing lens 2, the slit diaphragm 3 and the projection lens 4 and then impinges on the mirors I and 8. The

mirror I is attached to the thread feeler 5 which flexes to a greater or lesser extent according to the tension of the thread 9 passing over the rollers l8, and in known manner deflects the beam reflected by the mirror. A part of the beam is projected by the obliquely positioned mirror l2 onto the observation plate I4, whilst the remainder of the beam passes by mirror l2 and is collected in the lens l3 and focused on the sensitized paper strip I5 at a given point. By moving the photographic paper in the direction of the arrow (Fig. l) the thread tension graph line l6 indicating the varying tension of thread 9 over a given length of its passage through its working machine is produced.

At the same time a beam of light is reflected by mirror 8 of spring 6 partly onto plate l4 and scale I8 (Fig. l) and partly onto paper strip l5,

7 thus producing first a continuous base line H.

Now if it should be desired to indicate the thread tension between given points in the machine in which the thread is worked and as the thread passes between these points, a contact is made and a circuit is closed thereby into which the energizing winding of electromagnet H (Fig. l) is connected. Every time such a contact is made, spring armature 6 is attracted and thus the light beam reflected by mirror 8 is momentarily deflected and produces one of the kinks shown in base line H. Such a deflection also becomes visible on scale- I8. The contact mechanism by which magnet l l is energized forms no part of the present invention and is not shown here. It is suflicient to state that the electromagnet ll provides means by which definite portions or points of the thread relatively to their positions in the working machine can be designated when the tension graph is produced so that the existing tension at these points can be ascertained.

Fig. 2 shows a particularly handy form of apparatus of pistol-like shape which enables the appliance to be held in one hand. The strip of sensitized paper is wound from the supply reel 28 onto the take-up reel 29 and both reels can be removed by withdrawing the supporting studs 41. The speed of travel of the strip of sensitized paper can be varied by changing the gear wheels 24, 25 for others, these wheels being detachably mounted. The appliance is adapted to be applied to the thread to be tested while the latter is in operation in its working machine so that there is no interruption in the spinning, winding or weaving operation or whatever it may be. Owing to the tapered shape of the fingers 38, 39 the thread will be automatically guided to engage the pulleys l 8 and feeler 5 when the appliance is applied to the thread to be tested. The pulleys are mounted in jewel bearings so that they will run easily and with a view to reducing wear.

The degree of sensitiveness of the appliance can be varied by varying the degree of adjustment of the members 38 about their trunnions with consequent variation in the deflection of the thread, such adjustment being indicated by the pointer 42 and scale 44. Fig. 4 shows the maximum deflection of the thread by such adjustment and corresponds to the position I on the scale.

What I claim as my invention and desire to secure by Letters Patent of the United States is:

1. An appliance for testing the tension of textile threads while the latter are operated upon, comprising three tension fingers disposed to deflect the thread between them so as to cause the thread to exert its tension against the fingers, a spring feeler of extremely small mass and having a high natural vibration frequency, disposed in the middle finger to contact with the thread to respond to the tension effect of the latter, a mirror directly attached to said feeler, a source of light disposed to project a beam of light onto said mirror so as to be reflected by the latter, and a movable recording screen disposed to receive the reflected beam and means for moving said screen to produce a graph thereon by said beam, corresponding in its rise and fall to the varying tension of the thread.

2. An appliance for testing the tension of textile threads while the latter are operated upon, comprising three tension fingers disposed to deflect the thread between them so as to cause the thread to exert its tension against the fingers, a spring feeler of extremely small mass and having a high natural vibration frequency, disposed in the middle finger to contact with the thread to respond to the tension effect of the latter, a mirror directly attached to said feeler, a source of light disposed to project a beam 01! light onto said mirror so as to be reflected by the latter, a movable recording screen disposed to receive the reflected beam and means for moving said screen to produce a graph thereon by said beam, corresponding in its rise and fall to the varying tension of the thread, means for reflecting from said light source a second beam onto said screen to normally form a base line coextensive with said graph, and means for actuating said second reflecting means for deflecting said second beam at given points of the thread path to produce marks on said base line so as to indicate by the graph portion between two successive base line marks the tension condition of the thread.

3. An appliance for testing the tension of textile threads while the latter are operated upon, comprising three tension fingers disposed to defleet the thread between them so as to cause the thread to exert its tension against the fingers, said three fingers being pointed at their outer ends to permit the slipping of the fingers onto the thread and the deflection thereof, a thread guide housed in each outer finger and a spring feeler of extremely small mass and having a high natural vibration frequency, disposed in the middle finger to contact with the thread STEFAN FURS'I. 

